Finding the best herbicide for flax is essential for maintaining healthy crops and maximizing yields. Flax is highly susceptible to weed competition, making effective herbicide selection crucial for weed control.

Flax is a delicate yet profitable crop, but weeds like wild oats, kochia, and Canada thistle can reduce yield and quality if not managed properly.

Whether you need a pre-emergent, post-emergent, selective, or non-selective herbicide, choosing the right flax herbicide  depends on weed type, growth stage, and soil conditions.

This guide explores the 10 best herbicides for flax, providing in-depth reviews, manufacturer specifications, pros, and cons to help you make the best choice for your flax farm.

Tips for Choosing the Best Herbicide for Flax

1. Understand Weed Spectrum: Identify the predominant weed species in your field to select a herbicide that effectively targets them.
2. Herbicide Selectivity: Opt for selective herbicides that eliminate weeds while preserving the flax crop.
3. Application Timing: Determine whether a pre-emergent or post-emergent herbicide is suitable based on the growth stages of both flax and weeds.
4. Resistance Management: Rotate herbicides with different modes of action to prevent weed resistance.
5. Soil and Environmental Conditions: Consider soil type, pH, and moisture levels, as they can influence herbicide efficacy.
6. Regulatory Approvals: Ensure the herbicide is registered and approved for use on flax in your region.
7. Cost-Effectiveness: Balance the herbicide’s cost with its effectiveness and the potential economic benefits of weed control.

10 Best Herbicide For Flax

1. Buctril M – Best Selective Herbicide for Flax

Buctril M is a widely trusted selective herbicide among flax growers. It combines bromoxynil (Group 6) and MCPA (Group 4) to target over 28 broadleaf weeds without harming the flax crop. This dual-action formula ensures both contact and systemic control, enhancing its effectiveness.

The herbicide is particularly effective against weeds like kochia, wild buckwheat, and lamb’s-quarters. Its application window spans from the 5 cm height stage of flax up to the early flower bud stage, providing flexibility in weed management. Buctril M’s proven performance and crop safety make it a staple in flax cultivation.

Available in various packaging options, including 8 L jugs and bulk containers, Buctril M offers convenience for farms of all sizes. Its compatibility with multiple tank mix partners further enhances its utility in integrated weed management programs.

• Pros:
  • Controls 28 broadleaf weeds
  • Excellent crop safety
  • Dual modes of action
  • Flexible application timing
  • No re-cropping restrictions
  • Registered for aerial application
  • Available in bulk packaging
• Cons:
  • Requires specific application conditions
  • Potential crop injury under extreme conditions
  • Limited to certain weed species

2. Roundup WeatherMAX – Best Non-Selective Herbicide for Flax

Roundup WeatherMAX, containing glyphosate, is a potent non-selective herbicide ideal for pre-plant weed control in flax fields. Its systemic action ensures thorough eradication of a wide range of weeds, including perennials and annuals. Applying this herbicide before flax emergence helps establish a clean seedbed.

The herbicide’s rainfastness within 30 minutes and its ability to perform under various environmental conditions make it a reliable choice. Its advanced formulation allows for lower application rates while maintaining high efficacy, contributing to cost savings.

Roundup WeatherMAX is also known for its compatibility with various tank mix partners, enhancing its versatility in integrated weed management strategies. However, caution is necessary to prevent drift onto neighboring crops or non-target areas.

• Pros:
  • Broad-spectrum weed control
  • Fast rainfastness
  • Systemic action
  • Lower application rates
  • Cost-effective
  • Compatible with tank mixes
  • Reliable performance
• Cons:
  • Non-selective; affects all vegetation
  • Risk of drift
  • Requires careful handling

3. Aim EC – Best Contact Herbicide for Flax

Aim EC, with the active ingredient carfentrazone-ethyl (Group 14), is a contact herbicide effective against broadleaf weeds in flax cultivation. Its mode of action disrupts cell membranes, leading to rapid desiccation of targeted weed tissues. This fast-acting herbicide is particularly useful for controlling small, actively growing weeds.

The herbicide’s efficacy is enhanced when applied under sunny conditions, as light accelerates its action. Aim EC is often used as a tank mix partner to broaden the spectrum of weed control and manage herbicide resistance. Its minimal residual activity allows for rotational flexibility in cropping systems.

However, as a contact herbicide, thorough coverage is essential for optimal results. Applicators should ensure that spray equipment is calibrated correctly to achieve uniform application across the field.

• Pros:
  • Rapid action
  • Effective on broadleaf weeds
  • Minimal residual activity
  • Useful tank mix partner
  • Enhances resistance management
  • Flexible in crop rotations
  • Low use rates
• Cons:
  • Requires thorough coverage

4. Assure II – Best Grass Herbicide for Flax

Assure II is a selective post-emergent herbicide that targets grassy weeds in flax fields. Its active ingredient, quizalofop-p-ethyl (10.3%), is highly effective against foxtail, barnyardgrass, and wild oats. This systemic herbicide moves through the plant, ensuring complete eradication of invasive grasses.

Flax farmers in Texas, Missouri, and Georgia benefit from Assure II’s rapid absorption, making it ideal for USDA Zones 6-9. It works best when applied in the early post-emergence stage, allowing flax to thrive without grass competition. Proper tank mixing with broadleaf herbicides improves its overall effectiveness.

A key advantage of Assure II is its flexibility in crop rotation, allowing flax growers in Arizona, Florida, and California to maintain sustainable production cycles. It has no soil residual activity, making it safer for subsequent crops. However, it requires adequate coverage and is less effective on broadleaf weeds.

• Pros:
  • Targets grassy weeds
  • Quick absorption
  • Systemic action
  • No residual effect
  • Flexible crop rotation
  • Compatible with broadleaf herbicides
  • Ideal for post-emergence
• Cons:
  • Requires surfactant
  • Ineffective on broadleaf weeds
  • Reapplication may be needed

5. Raptor – Best Broadleaf Herbicide for Flax

Raptor is a selective post-emergent herbicide designed for broadleaf weed control in flax fields. Its active ingredient, imazamox (12.1%), is a Group 2 herbicide that inhibits acetolactate synthase (ALS), preventing weed growth. It effectively controls lambsquarters, pigweed, and kochia, common in USDA Zones 4-10, including Missouri and Texas.

Flax farmers in Arizona and Florida benefit from Raptor’s residual soil activity, which suppresses new weed germination. It is absorbed through foliar and root uptake, providing dual-action protection. For best results, it should be applied early post-emergence, when weeds are still small.

One of Raptor’s strengths is its low toxicity to flax, making it safer than non-selective herbicides. However, its performance is reduced in cool conditions, and resistant weed populations may develop with repeated use. A tank mix with Assure II improves overall weed control.

• Pros:
  • Targets broadleaf weeds
  • Residual soil activity
  • Dual uptake mechanism
  • Low toxicity to flax
  • Works in warm climates
  • Compatible with grass herbicides
  • Effective in USDA Zones 4-10
• Cons:
  • Reduced performance in cold
  • Potential for weed resistance
  • Requires tank mixing for full control

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6. Spartan – Best Pre-Emergent Herbicide for Flax

Spartan is a pre-emergent herbicide containing sulfentrazone (62.1%), a PPO inhibitor (Group 14) that controls broadleaf and grass weeds before they emerge. It provides long-lasting soil residual activity, making it ideal for USDA Zones 5-9, including Missouri, Texas, and California.

Flax farmers apply Spartan before planting, ensuring a weed-free start to the growing season. It works by inhibiting cell membranes, preventing weed seedlings from emerging. This herbicide is highly effective against kochia, waterhemp, and nightshade, which are common in warm climates like Arizona and Florida.

Spartan’s broad-spectrum control reduces the need for multiple applications, saving flax farmers time and costs. However, it requires moisture activation and may cause temporary flax stunting if applied at high rates. A proper application strategy is essential for maximizing results.

• Pros:
  • Pre-emergent control
  • Long residual activity
  • Broad-spectrum weed control
  • Reduces weed pressure
  • Ideal for USDA Zones 5-9
  • Effective in warm climates
  • Saves time and costs
• Cons:
  • Needs moisture activation
  • May cause crop stunting
  • Less effective in dry soil

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7. Basagran – Best Post-Emergent Herbicide for Flax

Basagran is a post-emergent broadleaf herbicide with bentazon (44%), a Group 6 PSII inhibitor that controls yellow nutsedge, mustard, and nightshade. It is ideal for flax growers in Texas, Missouri, and Florida, providing selective weed control without harming crops.

This contact herbicide works by disrupting photosynthesis, causing rapid wilting and weed death. It is rainfast within 4 hours, ensuring reliable results even in humid climates like Georgia and California. For best performance, it should be applied when weeds are actively growing.

Basagran does not provide soil residual activity, making it safer for crop rotation. However, it requires thorough coverage, and multiple applications may be needed for perennial weeds. It is often tank-mixed with Assure II for complete weed control.

• Pros:
  • Targets broadleaf weeds
  • Rainfast in 4 hours
  • Selective for flax
  • Effective in humid climates
  • Safe for crop rotation
  • No soil residual effect
  • Compatible with grass herbicides
• Cons:
  • No residual control
  • Needs thorough coverage
  • May require multiple applications

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8. Liberty 280 SL – Best Non-Selective Herbicide for Flax

Liberty 280 SL is a non-selective contact herbicide containing glufosinate-ammonium (24.5%), a Group 10 herbicide that disrupts amino acid synthesis. It is widely used for burndown applications in flax fields before planting in states like Arizona, Texas, and Georgia.

This herbicide provides rapid weed kill within hours of application, making it effective against both grass and broadleaf weeds. It is a great alternative to glyphosate, offering resistance management benefits. However, it works best under warm, sunny conditions, common in USDA Zones 6-10.

Liberty 280 SL requires thorough coverage for optimal results, and multiple applications may be needed for regrowth. It does not provide soil residual control, so it is best combined with pre-emergent herbicides like Spartan for season-long protection.

• Pros:
  • Non-selective control
  • Works in hours
  • Resistance management
  • Effective in warm climates
  • Alternative to glyphosate
  • Ideal for burndown
  • Compatible with pre-emergents
• Cons:
  • No soil residual effect
  • Needs thorough coverage
  • May require multiple applications

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9. Stinger – Best Regulator Herbicide for Flax Growth

Stinger, containing clopyralid (40.9%), is a growth regulator herbicide (Group 4) that targets thistle, ragweed, and mustard in flax fields. It works by disrupting plant hormones, causing uncontrolled growth and weed death.

Flax farmers in USDA Zones 4-9, including Missouri, Texas, and California, benefit from Stinger’s high selectivity. It is absorbed through leaves and roots, providing systemic control for long-term weed suppression. It is best applied during early vegetative stages.

Stinger is safe for flax but should not be over-applied, as excessive rates may cause crop injury. It requires a tank mix for broader weed control and is often paired with Assure II or Basagran.

• Pros:
  • Selective for flax
  • Systemic weed control
  • Targets tough weeds
  • Long residual activity
  • Ideal for early growth stages
  • Absorbed through roots & leaves
  • Works in USDA Zones 4-9
• Cons:
  • Risk of crop injury
  • Needs tank mixing
  • Slow weed kill

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10. Dual II Magnum – Best Soil-Applied Herbicide for Flax

Dual II Magnum, with metolachlor (83.7%), is a soil-applied herbicide that controls grass and small-seeded broadleaf weeds before they emerge. It works by inhibiting shoot growth, making it ideal for pre-plant or pre-emergence applications.

Flax farmers in Texas, Arizona, and Georgia benefit from its long residual activity, preventing weeds from competing with flax seedlings. It is highly effective in warm climates and is best used in USDA Zones 5-10.

Although Dual II Magnum provides excellent weed control, it does not target large-seeded broadleaf weeds and requires adequate soil moisture for activation. A tank mix with post-emergent herbicides is often recommended.

• Pros:
  • Long residual activity
  • Pre-emergent control
  • Ideal for USDA Zones 5-10
  • Reduces weed competition
  • Effective in warm climates
  • Works on grass & broadleaf
  • Safe for flax
• Cons:
  • Needs soil moisture
  • Ineffective on large-seeded weeds
  • Requires tank mix for full control

Best Herbicide for Flax FAQs 

1. What is the best pre-emergent herbicide for flax?
   The best pre-emergent herbicide for flax is Spartan (Sulfentrazone), which effectively controls broadleaf weeds and grasses before they emerge.
2. Which post-emergent herbicide works best for flax?
   Basagran (Bentazon) is a top post-emergent herbicide for flax, targeting broadleaf weeds without harming the crop.
3. Can I use glyphosate as a flax herbicide?
   Glyphosate can be used as a pre-plant burndown to eliminate weeds before seeding, but it is not safe for use on growing flax plants.
4. What is the best selective herbicide for flax?
   Raptor (Imazamox) is a selective herbicide that effectively controls broadleaf weeds and grasses while keeping flax unharmed.
5. Is there an organic herbicide for flax?
   Yes, vinegar-based herbicides or products like Weed Slayer offer organic weed control, but they may require multiple applications.
6. How do I prevent herbicide resistance in flax?
   To prevent resistance, rotate herbicides with different modes of action, use tank mixes, and apply herbicides at the recommended rates.
7. When is the best time to apply herbicides to flax?
   Pre-emergent herbicides should be applied before planting, while post-emergent herbicides work best when weeds are young and actively growing.

Conclusion

Choosing the right herbicide for flax farming is essential for achieving maximum yield and weed-free fields. Whether you need a pre-emergent, post-emergent, selective, or non-selective solution, herbicides like Assure II, Raptor, Spartan, Basagran, and Liberty 280 SL offer effective control against grasses and broadleaf weeds.

Each product has its strengths, from long residual activity to rapid weed kill, making it important to select the right herbicide based on climate, soil conditions, and weed pressure.

By integrating tank mixes and rotation strategies, flax farmers can ensure sustainable weed management and prevent herbicide resistance. Make informed decisions to protect your crops and boost productivity with the best herbicides for flax farming